Australian Prime Minister Julia Gillard has announced a federal election for Saturday, September 14.

In a surprise move, Gillard broke with tradition to set the election date months before the polling date - effectively setting the country up for a campaign season lasting more than eight months.

"Time is not for wasting. So decisions have to be made about how we use our time this year," Gillard told the National Press Club in Canberra.

This is well before the latest possible election date for the House of Representatives of November 30, 2013.

The writs for the election will be issued on August 12, setting up a short parliamentary year until the election. This will see the House of Representatives dissolved and half the Senate up for re-election.

Gillard said that last year Australians' patience was tried by "months of boiling hot political debate with most of it somewhat ironically about global warming".

"In 2013, I am determined their patience is not tried again," she said.

She said that not everything about the "tenor and temperature" of the debate in the coming election year was in her control.

"But I can act to clear away the carry-on that comes with speculation about when the election will be held," she said.

"I can create an environment in which the nation's eyes are more easily focused on the policies, not the petty politics. I can act so Australia's Parliament and government serves their full three-year-term."

Gillard said that she had always said that the parliament would serve a full term.

"There's only a limited number of dates on which the election could held," Gillard said, saying she had thought about the election date over the summer.

She said she had consulted Treasurer Wayne Swan and a few senior colleagues about the election date.

The move has been welcomed by independent MPs Rob Oakeshott and Tony Windsor.

"The early announcement of the federal election date of September 14 is good for the nation," Windsor said.

"I congratulate the Prime Minister on her decision to provide the Australian people with some direction and certainty as to when they will go to the polls."

Former Queensland premier Anna Bligh similarly broke with precedent by announcing last year's state election date early, but not with such a long lead time.

On January 25 last year, Bligh announced she would visit the Governor on February 19 to request the dissolution of Queensland Parliament with an election to follow on March 24.

In that case, Bligh justified the early announcement by saying it was needed to give certainty and ensure voters were able to see the final report of inquiry into the devastating 2010-11 floods.